Relatives of jailed Iranian human rights campaigner Narges Mohammadi and the Nobel Peace Prize Committee have called for her to be transferred to adequate medical facilities following a sharp reported deterioration of her health.

Her family said the 54-year-old had been taken from her prison in north-west Iran to a local hospital, calling the move a "last-minute" action that may come too late.

Mohammadi's brother Hamidreza, who lives in Norway, told the BBC's Newshour programme he fears she is dying, and that he wakes up "waiting for the worst call" he could get.

Narges Mohammadi was awarded the 2023 Nobel Peace Prize. She was arrested in December for her criticism of the authorities.

Last month, Hamidreza Mohammadi said his sister had been found unconscious by fellow inmates at Zanjan Prison in north-west Iran, after suffering a suspected heart attack.

He added that prison officials had refused to transfer her to a hospital despite her history of cardiac, lung and blood pressure problems.

The Narges Mohammadi Foundation, run by her family, said on Friday that she had been transferred to a hospital in Zanjan province "following a catastrophic deterioration in her health".

The statement added that it came "after 140 days of arbitrary detention and the persistent denial of specialised healthcare".

On Saturday, Hamidreza Mohammadi told the BBC his sister was suffering from low blood pressure and had had a heart attack.

He said her previous conditions, including a pulmonary embolism and having undergone stenting and angiography, made "any treatment by the doctors in Zanjan effectively impossible".

He said his sister should be transferred to a hospital in Tehran "so that her own specialists, who have treated her previously, can take over her care".

The call was echoed by Jorgen Watne Frydnes, head of the Nobel Peace Prize committee, who told Reuters news agency that Mohammadi's life was at risk.

Speaking to Newshour, her brother criticised the Iranian government for deliberately stopping his sister from getting the medical help she needed.

"I have no doubt that the regime has decided to just get rid of people like Narges and other activists," he said.

Iranian authorities have not publicly responded to the accusation or to any part of the Mohammadi family's account.

Her brother also said he believed the war in Iran had diverted attention away from the plight of prisoners in the country, saying the international community seemed "reluctant to talk about the real problem".

"It seems that oil is now more important than freedom," he said, referring to concerns over the key Strait of Hormuz trade route.

Narges Mohammadi has been arrested 13 times over her lifetime and sentenced to a total of 31 years in prison and 154 lashes, according to her foundation.

In 2021, she began serving a 13-year sentence on charges of committing "propaganda activity against the state" and "collusion against state security", which she denied.

In December 2024, she was given a temporary release from Tehran's notorious Evin prison on medical grounds.

She continued campaigning while undergoing treatment and was arrested in the north-eastern city of Mashhad last December after giving a speech at the memorial ceremony of a fellow human rights activist. Her family said she was taken to hospital after being beaten during the arrest.

In early February, Mohammadi was sentenced by a Revolutionary Court to an additional seven-and-a-half years in prison after being convicted of "gathering and collusion" and "propaganda activities", her lawyer said.

She was transferred without warning the following week to Zanjan prison and has been allowed only limited communication with her family since then.